Hyperfine-structure measurements in bismuth using a Fourier-transform spectrometer

Abstract

The spectrum of neutral bismuth has been studied in the infrared region by means of the Fourier-transform spectrometer at the Laboratoire Aimé Cotton, Orsay, France. A microwave-excited discharge tube containing bismuth iodide was used as the light source. A total of 37 hyperfine structures was studied. Precise measurements of the center of gravity of the structures give energy levels with an error less than 0.005 cm−1. Complete analysis of these hyperfine structures resulted in the determination of the magnetic-dipole and the electric-quadrupole interaction constants for 10 even and 12 odd levels. The present results have increased the number of newly classified lines to 78, as compared with 28 reported in our earlier work [ J. Opt. Soc. Am.72, 589 ( 1982)]. The analysis has also resulted in the confirmation and the assignment of many J values, improved values of energy levels, and two new levels.